eos Sleep NY: Snoring & Sleep Apnea Blog

Dimming Smartphone Brightness Can Help Sleep Better

Smartphones, iPads, and other personal electronic devices have added convenience and entertainment to our lives, but they may be negatively impacting the quality and quantity of sleep in our society.

New research from the Mayo Clinic in Scottsdale, AZ adds to previous studies that the brightly-lit screens of many personal mobile devices can interfere with melatonin, the hormone that helps control our sleep and wake cycles.

Melatonin is a hormone produced by the pineal gland at night and when it is dark. It is a “timer” that tells the body that it is nighttime, and time to go to sleep. Exposure to light at night, especially short-wavelength light, can slow or even stop melatonin production, interrupting sleep.

As personal electronic devices have become more ubiquitous, the bright-light emitting screens that allow the use of mobile devices in dimly lit rooms have become a more common reason for sleep disruption, whether users realize it or not.

About the Study

Lois Krahn, M.D., a psychiatrist and sleep expert at the Mayo Clinic and co-author of the study said, “In the old days, people would go to bed and read a book. More commonly, people go to bed and they have their tablet on which they read a book or newspaper or look at material. The problem is it’s a lit device, and how problematic is the light source from the mobile device?”

That question prompted Dr. Krahn to wonder, is the light from screens always a negative factor for sleep?” To find out, Krahn and his colleagues experimented with two tablets and a smartphone in a dark room, using a meter on its most sensitive setting to measure the light the devices emitted at various settings when held various distances from a person’s face.

They discovered that when the brightness settings were lowered and the devices were held just over a foot from a user’s face, it reduced the risk that the light would be bright enough to suppress melatonin secretion and disrupt sleep.

Explains Krahn, “We found that only at the highest setting was the light over a conservative threshold that might affect melatonin levels. If it’s at the mid setting or at a low setting, it’s bright enough to use.”

The new Mayo Clinic research, which was presented in June at SLEEP 2013, the 27th annual meeting of the Associated Professional Sleep Societies LLC, in Baltimore, Md., also suggests things you can do to help prevent screen light from interfering with melatonin and affecting sleep.

These tips include dimming the smartphone or tablet brightness settings and holding the device at least 14 inches from your face while using it.

Other general tips include moving the TV and computer out of the bedroom, or at the very least, do not watch TV or work on the computer to bedtime. With so many electronic distractions in our lives, it’s important to re-claim the bedroom for its intended purpose: rest, relaxation, and sleep.